Heat Sealing Equipment

Abstract

The purpose of the present invention is to provide a heat-sealing device capable of preventing problems associated with cap sealing performance and / or sensation of the cap being open due to an inappropriate cap temperature. For this purpose, this heat-sealing device (10), which is used in a manufacturing apparatus (100) for manufacturing a product for which an opening part (1A: mouth part) of a container (1) is sealed with a cap (2), is provided with: a pressing plate (5) which is disposed on a path along which the containers (1) move; a heating unit (3) and sealing heads (4) for pressing the caps (2) sealing the containers (1), the heating unit (3) and sealing heads (4) being arranged on the pressing plate (5); a temperature measurement device (7) for measuring the temperatures of the sealing heads (4); and a control device (8: control unit) for transmitting control signals to a container conveyance drive source (for example, inverter) in accordance with the measurement results from the temperature measurement device (7).

Description

[Technical field]

[0001] The present invention relates to a heat sealing device, and more particularly to a heat sealing device having a function of performing optimal heat sealing based on the temperature of an elastic material in contact with a sealing member. [Background technology]

[0002] The opening (mouth) of a container (e.g., a resin container) that holds various beverages may be sealed with a cap (e.g., an aluminum cap) during the manufacturing process. Such sealing prevents the beverage, which is the content, from leaking and prevents foreign matter from entering the container or the beverage. Here, sealing the mouth of the container with a cap is performed by a filling machine on the manufacturing line.

[0003] A filling machine that fills beverages into containers is equipped with a cutting head, and a cap is placed on the filled container (crapping). At the time of crowning, the cap does not seal the container, but is simply placed on the container. When sealing a container placed on the conveying means after the cap has been placed thereon, the cap is first pressed against the container by the seal head. For example, if the cap is made of metal (aluminum, etc.), eddy currents are generated by electromagnetic induction, causing the cap itself to heat up. Hot melt is applied to the container side of the cap, and when heated, the hot melt melts and adheres the cap to the mouth of the container.

[0004] Here, an elastic material (e.g., silicone rubber) is arranged on the seal head that presses the cap so that the cap is evenly pressed against the container. The temperature of the elastic material was not particularly measured in the prior art, and a metal cap, for example, was adhered to the container with hot melt, regardless of the temperature of the elastic material. However, for example, even if the eddy current generated by electromagnetic induction is constant, if the temperature of the elastic material is low, the heat of the cap generated as a result of induction heating is absorbed by the elastic material, the temperature of the cap does not rise, the hot melt does not bond the cap sufficiently, and problems with sealing occur (resulting in "poor sealing"). Also, if the amount of induction heating is set large in accordance with the case where the temperature of the elastic material is low, when the temperature of the elastic material rises, problems such as the seal becoming too strong and / or the container flange melting occur, causing problems when opening (resulting in "poor sealing" and / or "problems with the opening feeling").

[0005] As another conventional technique, a heat sealing device that measures the temperature of a sealing head and adjusts the temperature to an appropriate temperature is disclosed (see Patent Document 1). However, this conventional technique cannot prevent the occurrence of problems such as poor sealing and feeling of opening as described above. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2004-189323 A Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been proposed in consideration of the problems of the prior art described above, and aims to provide a heat sealing device that can prevent problems such as poor sealing or a feeling of opening caused by inappropriate heating of the cap. [Means for solving the problem]

[0008] The heat-sealing device (10) of the present invention is used in a manufacturing device (100) for manufacturing a product in which an opening (1A: mouth portion) of a container (1: for example, a resin container) is sealed with a cap (2: for example, an aluminum cap), A pressure plate (5) is provided on the path along which the container (1) moves. The heating method of the cap (2) is induction heating, The pressure plate (5) is provided with a seal head (4) for pressing the cap (2) placed on the container (1) and a heating section (3) for generating heat in the cap (2) by induction heating. a temperature measuring device (7: for example, a non-contact infrared radiation thermometer) that measures the temperature of the sealing head (4) and a control device (8: a control unit) that transmits a control signal to a container conveyance drive source (for example, an inverter) based on the measurement result of the temperature measuring device (7); the control device (8) has a function of adjusting the moving speed of the container (1) in accordance with the temperature of the sealing head (4), slowing down the moving speed when the temperature of the sealing head (4) is low, and increasing the moving speed when the temperature of the sealing head (4) is high, thereby adjusting the heating time of the cap (2); A container detection sensor (9) is provided upstream of the temperature measuring device (7) (the side where the container 1 is supplied), After a certain time has elapsed since the container detection sensor (9) detected the container (1), the temperature measuring device (7) starts measuring the temperature of the sealing head (4), At the start of sealing, a control signal from the control device (8) is sent to a container conveyance drive source (e.g., an inverter) and adjustment of the moving speed of the container (1) is completed. A silicone rubber (6) is disposed at a portion of the sealing head (4) that comes into contact with the mouth of the container, and the temperature measuring device (7) has a function of measuring the temperature of the silicone rubber (6); The temperature measuring device (7) has a function of measuring the temperature of all the seal heads (4) of the pressure plate (5), The control device (8) has a function of identifying the lowest temperature among the measured temperatures of the silicone rubber (6) in each of all the seal heads (4) in order to prevent sealing failure that occurs when the seal heads (4) are at a low temperature; The control device (8) has a function of judging whether the minimum temperature is lower than a lower limit temperature, which is a temperature at which the temperature of the cap (2) does not decrease, the adhesive strength of the hot melt does not become insufficient, and there is no problem with the sealing between the cap (2) and the container (1), or higher than an upper limit temperature, which is a temperature at which the temperature of the cap (2) does not become too high, and there is no problem with the opening feeling, such as melting the flange part of the container (1) during sealing, or a temperature between the lower limit temperature and the upper limit temperature, The time from when the container detection sensor (9) detects the container (1) to when the sealing starts is the time from when the container (1) is detected to when the temperature is measured, All of the above This time is characterized by being the sum of the time required to complete temperature measurement of the silicone rubber (6) and the time required for the movement speed of the container (1) to actually be switched after a control signal for switching the container movement speed is sent from the control device (8).

[0011] In the present invention, The sealing heads (4) are arranged circumferentially on the pressure plate (5), and the container (1) in contact with the sealing heads (4) preferably moves in accordance with the rotation of the pressure plate.

[0012] In the method using the heat sealing apparatus (10) of the present invention described above, The temperature of the seal head (4) is measured using a temperature measuring device (7: for example, a non-contact infrared radiation thermometer). A control signal is sent to a container conveyance drive source (e.g., an inverter) based on the temperature measurement result of the sealing head (4); The heating time of the cap (2) is determined according to the temperature of the seal head (4). Effect of the Invention

[0013] According to the present invention having the above-mentioned configuration, since there is a temperature measuring device (7: for example, a non-contact infrared thermometer) that measures the temperature of the sealing head (4) and a control device (8: control unit) that has a function of adjusting the moving speed of the container according to the temperature of the sealing head (4), for example, when the temperature of the sealing head (4) is low, it is possible to raise the temperature of the cap (2) to a desired temperature by slowing down the moving speed of the container (1) and lengthening the heating (for example, induction heating) time. As a result, the cap (2) is reliably bonded to the container (1) by the hot melt, and poor sealing can be prevented. On the other hand, when the temperature of the sealing head (4) is high, the moving speed of the container (1) is increased, thereby shortening the time for heating the cap (2) (e.g., induction heating). This keeps the temperature of the cap (2) within an appropriate range, preventing problems such as an excessively strong seal or melting of the flange of the container (1), and preventing problems such as a feeling of opening or poor sealing. In other words, in the present invention, the moving speed of the container (1) is controlled using the temperature of the elastic material (6) arranged on the pressure plate (5) as a parameter, thereby making it possible to prevent problems such as poor sealing and a feeling of opening.

[0014] In the present invention, a container detection sensor (9) is provided upstream of the temperature measuring device (7) (the side where the container 1 is supplied), After a certain time has elapsed since the container detection sensor (9) detected the container, the temperature measuring device (7) starts measuring the temperature of the sealing head (4), At the start of sealing, a control signal from the control device (8) is sent to the container conveying drive source (e.g., an inverter), and once adjustment of the container conveying speed has been completed, heat sealing can be performed efficiently at the appropriate timing. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is an explanatory diagram showing a production line to which an embodiment of the present invention is applied. [Diagram 2] FIG. 2 is a plan view showing a filling machine in the production line of FIG. 1. [Diagram 3] 2 is an enlarged front view showing the main parts of the filling machine. FIG. [Figure 4] FIG. 2 is a block diagram of the filling machine. [Diagram 5] 4 is a flow chart showing the control of the illustrated embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In the illustrated embodiment, the container 1 is made of resin, the cap 2 is made of aluminum, and the elastic material 6 is made of, for example, silicone rubber. However, the container 1, the cap 2, and the elastic material 6 may be made of other materials.

[0017] In Fig. 1, a manufacturing apparatus 100 is equipped with a filling machine 20, which fills a container 1 with beverage and seals it after a cap is placed on it (after crown capping). At the crown capping stage, the cap 2 is simply placed on the container 1 and is not bonded to the container 1, so the filling machine 20 is equipped with a heat sealing device 10, which bonds the cap 2 to the container 1. In the manufacturing apparatus 100, inspection devices and manufacturing equipment are installed before and after the filling machine 20 as necessary. Although not clearly shown in the figure, the straightening machine 30 has a function of aligning the openings (mouths) of the containers 1 so that they face upward, and sending them out in sequence to the next process.

[0018] Here, the filling machine 20 has a filling section 21, an intermediate star wheel 22, and a sealing section 23 (see FIG. 2). The path of the container 1 (see FIGS. 3 and 4) moving through the filling machine 20 is indicated by an arrow A in FIG. The area indicated by the symbol B (shown as a broken circle) of the intermediate star wheel 22 is an area where the cap 2 formed by the cutting head 24 (see FIG. 1) is capped onto the container 1. The wheel-shaped sealing unit 23 includes a heat-sealing device 10, which includes a heating unit 3 that heats the cap 2 placed on the container 1. A thermoplastic resin (hot melt) is applied to the container side of the cap 2, and the hot melt melts when heated by the heating unit 3, thereby bonding the cap 2 to the container 1.

[0019] In Figure 3, the heat sealing device 10 of the sealing section 23 (Figure 2) of the filling machine 20 has a heating section 3, a circular pressure plate 5, and a seal head 4, and the seal head 4 forms part of the pressure plate 5 and has the function of pressurizing the aluminum cap 2 placed on the container 1. The pressure plate 5 has a disk shape having a central axis C, and as shown in Fig. 4, a plurality of (e.g., 36) seal heads 4 are provided in the circumferential direction near the outer periphery of the pressure plate 5. Fig. 3 shows only one of the seal heads 4 that are present in the circumferential direction of the pressure plate 5. A storage section 4A is formed on the container 1 side of the seal head 4 (the lower side in FIG. 3), and a silicone rubber 6, which is an elastic material, is disposed in the storage section 4A. Details of the silicone rubber will be described later. The movement path of the multiple seal heads 4 of the pressure plate 5 constitutes a part of the transport path of the container 1 in the sealing section 23 (FIG. 2). While rotating around the central axis C, the pressure plate 5 presses the aluminum cap 2 against the container 1 via the silicone rubber 6 of the seal head 4, thereby transporting the container 1.

[0020] As shown in FIG. 3, an aluminum cap 2 is placed over the upper mouth 1A (opening) of the container 1 placed on the conveying means 11, and as described above, the cap 2 is pressed against the container 1 (the lower side in FIG. 3) via silicone rubber 6. Hot melt (indicated by the symbol HM in Figure 3) is applied to the container 1 side of the cap 2, and the aluminum cap 2 heats up by induction heating from a heating unit 3 installed in the transport path of the container 1, melting the hot melt HM and adhering the cap 2 to the mouth 1A of the container 1. A heating coil 3A constituting the heating unit 3 is disposed above the pressure plate 5. A primary magnetic field MF1 is generated in the heating coil 3A by passing a high-frequency current through the heating coil 3A, and when a secondary magnetic field MF2 is generated in the seal head 4 by the primary magnetic field MF1, a tertiary magnetic field MF3 is generated in the aluminum cap 2, and an eddy current is generated in the aluminum cap 2 by the tertiary magnetic field MF3, causing the aluminum cap 2 to heat up. Although not clearly shown, a heating coil 3A and a means for supplying high frequency current (not shown) are disposed above the seal head 4 of the pressure plate 5 shown in FIG.

[0021] In the illustrated embodiment, the pressure plate 5 is disk-shaped, the seal heads 4 are arranged circumferentially inside the pressure plate 5, and the heating method is induction heating. However, there are no particular limitations to either configuration, and the seal heads 4 may be arranged linearly, for example, and the heating method may be induction heating or not, and can be set appropriately depending on other configurations. Although silicone rubber 6 has been exemplified as the elastic material arranged in the housing section 4A below the pressure plate 5, the elastic material is not particularly limited as long as it is a material that has elasticity, heat resistance, releasability (property of not adhering to the mold), insulation (non-conductivity), and hygiene. In other words, silicone rubber is an example of a material that has such properties, and the surface of silicone rubber may be processed with fluororesin (Teflon (registered trademark)).

[0022] 3, when the aluminum cap 2 is pressed against the container 1 via the silicone rubber 6, as described above, if the temperature of the silicone rubber 6 in contact with the aluminum cap 2 is low, the heat of the aluminum cap 2 is absorbed by the silicone rubber 6. As a result, the temperature of the aluminum cap 2 does not rise, the hot melt does not melt sufficiently, and the sealing performance at the sealing or bonding portion between the aluminum cap 2 and the container 1 becomes insufficient. On the other hand, if the temperature of the silicone rubber 6 is too high, the seal or adhesion between the aluminum cap 2 and the container 1 becomes too strong and / or the flange portion of the container 1 melts, or other problems occur.

[0023] In Figure 4, a temperature measuring device 7 (temperature sensor) is provided at the downstream end (the right end in Figure 4) of the sealing section 23, and the temperature sensor 7 has the function of measuring the temperature of the nearby sealing head 4 and transmitting the measurement result to a control device 8 (control unit). The filling machine 20 also has a container detection sensor 9 and an inverter (container conveying drive source: not shown), and the inverter has the function of controlling and driving the rotational speed of the pressure plate 5 (i.e., the movement speed of the container 1) based on a control signal from the control unit 8. The container 1 flows through a filling section 21 and an intermediate star wheel 22, and is sealed (bonded) to the aluminum cap 2 (FIG. 3) and the container 1 in a sealing section 23. The path of the container 1 is indicated by an arrow A.

[0024] 4, in the sealing section 23, the container 1 is positioned corresponding to a plurality of seal heads 4 provided in the circumferential direction of the pressure plate 5. In other words, the container 1 (container 1 capped with cap 2) is placed below the location corresponding to the seal head 4, and the container 1 is transported through the sealing section 23 by the rotation of the pressure plate 5. The heating unit 3 is fixed and positioned in a partial area of ​​the pressure plate 5, and in Figure 4, the heating unit 3 is positioned above the pressure plate 5, and a heating coil 3A (see Figure 3) and a high-frequency current generating means (not shown) are also arranged.

[0025] In FIG. 4, a temperature sensor 7 provided near the outlet of the heating unit 3 (downstream end: right end in FIG. 3) detects the temperature of the silicone rubber 6 (elastic material, FIG. 3). Here, the temperature of the silicone rubber 6 is detected by using, for example, a non-contact infrared radiation thermometer. A known commercially available product can be used as the non-contact infrared radiation thermometer. The temperature measurement result of the silicone rubber 6 (the silicone rubber 6 in the seal head 4 near the outlet of the heating section 3) detected by the temperature sensor 7 is transmitted to a control device 8 (control unit) via a signal line SL1. The control unit 8 determines an appropriate rotation speed of the pressure plate 5 based on the temperature measurement results obtained from the temperature sensor 7, and transmits a control signal (a control signal related to the rotation speed of the pressure plate 5) to an inverter (container conveying driving source) not shown in the figure via the signal line SL2.

[0026] The rotation speed of the pressure plate 5, that is, the moving speed of the container 1, is controlled by transmitting a control signal (a control signal related to the rotation speed of the pressure plate 5) from the control unit 8 to an inverter (not shown). When the temperature of the silicone rubber 6 in contact with the cap 2 of the container 1 is low, the control unit 8 sends a control signal to an inverter (not shown) to slow down the rotation speed of the pressure plate 5. As a result, the moving speed of the container 1 slows down, the time for induction heating the aluminum cap 2 becomes longer, and the temperature of the cap 2 can be raised to the desired temperature, so that the aluminum cap 2 is reliably bonded to the container 1 by the hot melt.

[0027] On the other hand, if the temperature of the silicone rubber 6 is too high, the rotation speed of the pressure plate 5 is increased to increase the moving speed of the container 1. As a result, the time required for induction heating of the cap 2 is shortened, the hot melt is properly melted, and problems such as melting of the flange of the container 1 are prevented. Also, for example, it is possible to set the rotation speed of the pressure plate 5, ie, the moving speed of the container 1, in advance in accordance with the temperature of the silicone rubber 6, and change the rotation speed in accordance with the rise in temperature. Here, the moving speed of the container 1 may change continuously or intermittently according to the temperature of the silicone rubber 6. When the moving speed of the container 1 is changed intermittently, for example, a plurality of stages (for example, five stages) of the rotation speed of the pressure plate are set in advance according to the temperature measurement result of the temperature sensor 7.

[0028] 4, a container detection sensor 9 that detects the passage of a container 1 is disposed upstream of the heat-sealing device 10 (upstream of the entrance to the filling section 21 in the illustrated embodiment), and a detection signal from the container detection sensor 9 is transmitted to a control unit 8 via a signal line SL3. Here, the operation of the illustrated embodiment will be described with reference to FIG.

[0029] 4, when the container 1 moves to P1, a detection signal from the container detection sensor 9 is transmitted to the control unit 8. After receiving the detection signal, the control unit 8 transmits a signal to the temperature sensor 7 via SL1 to start measuring the temperature. In reality, a first time lag occurs between when the container 1 is detected and when the temperature is measured, and the container 1 has already moved to position P10 by the time when the temperature measurement starts.

[0030] In the illustrated embodiment, after measuring the temperatures of 36 pieces of silicone rubber 6, the rotation speed of the pressure plate 5 is determined based on the minimum temperature among the 36 measurement results. For example, from among rotation speeds (e.g., five stages of rotation speeds) preset according to the temperatures of the silicone rubber 6, a rotation speed corresponding to the relevant temperature of the silicone rubber 6 is selected. Then, a control signal corresponding to the selected rotation speed is sent from the control unit 8 to an inverter (not shown). The rotation speed of the pressure plate 5 is determined based on the minimum temperature among a large number of measurements (36 measurements of the temperature of the silicone rubber 6) because, in the illustrated embodiment, the primary objective is to prevent poor sealing that occurs when the seal head 4 is at a low temperature.

[0031] When the temperature measurement of the 36 silicone rubbers is completed, the container 1 first detected by the container detection sensor 9 moves from position P10 to position P46 (=10+36). That is, a second time lag is required for the time required to complete the temperature measurement of the 36 silicone rubbers. Furthermore, at the point of P46, the rotation speed of the pressure plate has not yet been changed, and from this point on, after the control unit 8 sends a control signal to the inverter to switch the rotation speed, a third time lag is required for the rotation speed of the pressure plate 5 to actually be switched (changed). The time lag 3 corresponds to the time required for the container 1, which was at the position P46, to move to the position P65 immediately before it flows into the heating unit 3.

[0032] As described above, in Fig. 4, a predetermined time corresponding to the sum of the first time lag, the second time lag, and the third time lag must elapse from when the container detection sensor 9 detects the container 1 until it enters the heating section. In other words, in order to complete setting of the rotation speed of the pressure plate 5 at the time when the container 1 enters the heating section, it is necessary to provide the container detection sensor at an appropriate position and start control. Since the first to third time lags vary depending on the number of sealing heads and the type of inverter, it is necessary to determine the first to third time lags in accordance with the above-mentioned configuration.

[0033] The control in the illustrated embodiment will be described mainly with reference to FIG. In FIG. 5, in step S1, container detection sensor 9 (FIG. 4) arranged at a predetermined position (position P1) in filling machine 20 determines whether or not a transported container 1 (FIGS. 3 and 4) has been detected. In step S1, if a container 1 is detected (step S1 is "Yes"), the process proceeds to step S2, and if a container 1 is not detected, step S1 is repeated (a loop in which step S1 is "No").

[0034] In step S2 (when the container detection sensor 9 detects the container 1), measurement of the temperature of the sealing head 4 (the temperature of the silicone rubber 6) by the temperature sensor 7 (FIG. 4) is started. The temperature measurement is performed sequentially for all (e.g., 36) sealing heads 4 of the pressure plate 5 (FIGS. 3 and 4). In the illustrated embodiment, the temperature measurement of the sealing head 4 is started a predetermined time (the "first time lag" described above with reference to FIG. 4) after the container 1 is detected in step S1. Then, the process proceeds to step S3. In step S3, it is determined whether or not the temperatures of all (36) seal heads 4 arranged at equal intervals in the circumferential direction of the pressure plate 5 have been measured. As a result of the judgment in step S3, if the temperature has been measured for all of the seal heads 4 on the pressure plate 5 (step S3 is "Yes"), proceed to step S4; if the temperature has not been measured for all of the seal heads 4 on the pressure plate 5 (temperature measurement has not been completed) (step S4 is "No"), return to step S2 and continue measuring the temperature of the seal heads 4.

[0035] In step S4 (when the temperatures of all the seal heads 4 of the pressure plate 5 have been measured), the minimum temperature is identified from the temperature measurement values ​​of the silicone rubber 6 in all (36) seal heads 4 of the pressure plate 5 measured in step S3. Then, it is determined whether the identified minimum temperature is within a predetermined range, is lower than a predetermined lower limit temperature, or is higher than a predetermined upper limit temperature. The optimal temperature range varies depending on the rotation speed of the pressure plate, but the "predetermined lower limit temperature" is the lowest temperature at which the temperature of cap 2 does not drop, the adhesive strength of the hot melt does not become insufficient, and there is no problem with the airtightness of the seal (glue) between cap 2 and container 1, and the "predetermined upper limit temperature" is the highest temperature at which the temperature of cap 2 does not become too high, causing problems such as melting of the flange part of container 1 during sealing, and causing problems with the feel when opened. Therefore, if the temperature is equal to or higher than a predetermined lower limit temperature and equal to or lower than a predetermined upper limit temperature (within a predetermined range), proper heat sealing can be achieved.

[0036] In step S4, if the minimum temperature is lower than the "predetermined lower limit temperature", proceed to step S5; if the minimum temperature is higher than the "predetermined upper limit temperature", proceed to step S6; if the minimum temperature is within the "predetermined range", proceed to step S7. In step S5 (if the minimum temperature is lower than the "predetermined lower limit temperature"), a control signal is sent to the inverter to reduce the rotation speed of the pressure plate 5 and reduce the moving speed of the container 1. By slowing down the moving speed of the container 1, the time for induction heating becomes longer, and an appropriate time for induction heating the cap 2 can be ensured. When step S5 is completed, proceed to step S8.

[0037] In step S6 (when the minimum temperature is higher than the "predetermined upper limit temperature"), a control signal is sent to the inverter to increase the rotation speed of the pressure plate 5 and increase the moving speed of the container 1. By increasing the rotation speed of the pressure plate 5, the time for induction heating the cap 2 is shortened, the adhesive strength of the hot melt is prevented from becoming too strong and is kept appropriate, and defects such as melting of the flange portion of the container 1 are prevented. After step S6 is completed, proceed to step S8. In step S7 (when the minimum temperature is within the "predetermined range"), the rotation speed of the pressure plate 5 is maintained, and the movement speed of the container 1 is maintained. When step S7 is completed, proceed to step S8.

[0038] Here, in the above-mentioned steps S4 to S7, the minimum temperature of the sealing head 4 is controlled to be "lower than the lower limit temperature", "higher than the upper limit temperature", and "within a predetermined range (above the lower limit temperature and below the upper limit temperature)", by "reducing the rotation speed of the pressure plate 5", "increasing the rotation speed of the pressure plate 5", and "maintaining the rotation speed of the pressure plate 5", respectively. Alternatively, the relationship between the minimum temperature of the seal head 4 and the rotation speed of the pressure plate 5 can be determined in advance, and the rotation speed of the pressure plate 5 can be determined based on the relationship and the minimum temperature of the seal head 4. Here, the relationship can be a table, an arithmetic expression, or the like. In step S8, it is determined whether or not to end the control shown in Fig. 5. Here, the criteria for determining whether to end the control can be arbitrarily set according to the embodiment. In step S8, if the control is not to be ended (No in step S8), the process returns to step S2, and the temperature measurement and the control of the rotation speed of the pressure plate 5 are continued.

[0039] According to the illustrated embodiment, the temperature of the silicone rubber 6 of the sealing head 4 is measured by a temperature sensor 7 (e.g., a non-contact infrared radiation temperature sensor), and if the temperature of the silicone rubber 6 is low, a control signal is sent to an inverter (container conveying drive source) to slow down the rotational speed of the pressure plate 5 (movement speed of the container 1), and if the temperature of the silicone rubber 6 is high, the rotational speed of the pressure plate 5 (movement speed of the container 1) is increased. Therefore, when the temperature of the silicone rubber 6 is low, the temperature of the cap 2 is prevented from dropping, and the cap 2 is heated to the desired temperature by induction heating, and the cap 2 is securely bonded to the container 1 by the hot melt, preventing poor sealing. On the other hand, when the temperature of the silicone rubber 6 is high, the rotation speed of the pressure plate 5 is increased to increase the moving speed of the container 1 and shorten the time for induction heating the cap 2, thereby keeping the temperature of the cap 2 within an appropriate range, preventing the seal from becoming too strong and preventing defects such as the flange portion of the container 1 melting. In other words, in the illustrated embodiment, the rotation speed of the pressure plate 5 of the filling machine 20 or the moving speed of the container 1 can be controlled using the temperature of the silicone rubber 6 (elastic material) arranged on the pressure plate 5 as a parameter, thereby providing a product that has no problems with sealing and opening feel.

[0040] In the illustrated embodiment, temperature measurement of the sealing head 4 is started based on a detection signal of the container 1 from the container detection sensor 9 arranged in the filling machine 20 and upstream of the temperature sensor 7 (heat sealing device 10). After the temperature measurement is completed (temperature measurement of all sheet heads 4 of the pressure plate 5), the rotation speed of the pressure plate 5 to be switched is determined based on the minimum temperature among all the measured values, and a control signal for the switching is sent to the inverter, which actually switches the rotation speed of the pressure plate 5. At this time, the control unit 8 starts control after detecting the container 1, and the detection position of the container is set to a position taking into account the first to third time lags, so that heat sealing is performed efficiently at the appropriate timing, preventing unnecessary power supply (unnecessary induction heating) or enabling induction heating to be performed reliably at the required timing.

[0041] In the illustrated embodiment, the relationship between the heating time of the cap 2 and the temperature of the silicone rubber 6 was confirmed using containers with mouths having outer diameters of 25 mm, 28 mm, and 35 mm. The heating time of the cap 2 and the temperature of the silicone rubber 6 were changed, and the sealing condition was confirmed at each time. The results are shown in Table 1 (mouth size: outer diameter 25 mm), Table 2 (mouth size: outer diameter 28 mm), and Table 3 (mouth size: outer diameter 35 mm). In addition, The symbol "○" indicates a proper seal. The symbol "x" indicates that the heating time was short and the cap was not sufficiently adhered. The "xx" symbol indicates that the seal was too strong and / or the container flange was melted. Table 1 TIFF0007633232000001.tif168157Table 2 TIFF0007633232000002.tif62111Table 3 TIFF0007633232000003.tif52111

[0042] As a result of Tables 1 to 3, it was found that the heating time can be adjusted by controlling the rotation speed of the pressure plate so as to satisfy the following formula. ((94.0-y)×((d+50) / 75)) / 39.6 <x <((102-y)×((d+50) / 75)) / 35.6 x: heating time of the cap (seconds), y: temperature of the silicon rubber 6 (℃), d: outer diameter of the mouth (mm) It has also been confirmed that the illustrated embodiment is applicable to containers with an outer diameter of the mouth size of 20 mm to 40 mm. In addition, if various conditions change depending on the processing capacity of the device, the shape and material of the cap, and the structure of the heating unit, the above formula must be reconstructed.

[0043] It should be noted that the illustrated embodiment is merely an example and is not intended to limit the technical scope of the present invention. [Explanation of symbols]

[0044] 1...container 1A...Opening (mouth) 2···Cap (aluminum cap) 3... Heating part 4. Seal head 5. Pressure plate 6. Elastic material (e.g., silicone rubber) 7. Temperature sensor (e.g., non-contact infrared radiation temperature sensor) 8. Control unit (control device) 9. Container detection sensor 10. Heat sealing device 100...Manufacturing equipment

Claims

1. A heat sealing device used in a manufacturing apparatus for producing a product in which the opening of a container is sealed with a cap, A pressure plate is provided on the path along which the container moves. The heating method of the cap is induction heating, The pressure plate is provided with a seal head for pressing a cap placed on a container, and a heating section for generating heat in the cap by induction heating. a temperature measuring device for measuring the temperature of the sealing head and a control device for transmitting a control signal to a container conveying drive source based on a measurement result of the temperature measuring device; the control device has a function of adjusting the moving speed of the container in accordance with the temperature of the sealing head, slowing down the moving speed when the temperature of the sealing head is low, and increasing the moving speed when the temperature of the sealing head is high, thereby adjusting the heating time of the cap; A container detection sensor is provided upstream of the temperature measuring device, After a certain time has elapsed since the container detection sensor detected the container, the temperature measuring device starts measuring the temperature of the sealing head. At the start of sealing, a control signal from the control device is sent to the container transport drive source, and adjustment of the container movement speed is completed; An elastic material is disposed at a portion of the sealing head that contacts the container mouth portion, and the temperature measuring device has a function of measuring the temperature of the elastic material, The temperature measuring device has a function of measuring the temperature of all the seal heads of the pressure plate, the control device has a function of identifying a minimum temperature from among the measured temperatures of the silicone rubber in each of all the seal heads in order to prevent a sealing failure that occurs when the seal head is at a low temperature; The control device has a function of judging whether the minimum temperature is lower than a lower limit temperature, which is a temperature at which the temperature of the cap does not drop and the adhesive strength of the hot melt does not become insufficient, and there is no problem with the sealing between the cap and the container, or higher than an upper limit temperature, which is a temperature at which the temperature of the cap does not rise too high, and there is no problem with the opening feeling, such as melting the flange part of the container during sealing, or a temperature between the lower limit temperature and the upper limit temperature, A heat sealing device characterized in that the time from when the container detection sensor detects a container to when sealing begins is the sum of the time from when the container is detected to when the temperature is measured, the time required for all of the silicone rubber temperature measurements to be completed, and the time required for the container movement speed to actually be switched after a control signal to switch the container movement speed is sent from the control device.

2. 2. The heat-sealing apparatus according to claim 1, wherein the sealing heads are arranged circumferentially on the pressure plate, and the containers in contact with the sealing heads move in accordance with the rotation of the pressure plate.

3. A heat sealing method using the heat sealing apparatus according to claim 1 or 2, The temperature of the seal head is measured by a temperature measuring device. Transmitting a control signal to a container conveying drive source based on the temperature measurement result of the sealing head; A heat sealing method characterized in that the heating time of the cap is determined depending on the temperature of the sealing head.

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